Urinary incontinence affects a sizeable portion of the elderly population; with the incidence of occurrence being highest among nursing home residents. The condition adversely affects the patient's physical and psychological well-being. Furthermore, the labor associated with the management of such patients has a significant economic impact on the nursing homes involved. The aim here is to develop a low-cost, ambulatory instrument that can significantly x-educe the number of accidents in incontinent patients. Using non-ionizing ultrasonic energy, the device will continuously monitor the volume of urine in the patient's bladder and automatically set-off an audible alarm whenever this volume exceeds a preset maximum. The patients can then perform (or be helped to perform) a controlled voiding - before an accident occurs. Furthermore, the feed-back capabilities of the device is expected to significantly improve the efficacy of both bladder and habit training programmes. It has the potential for significantly improving the quality and cost effectiveness of incontinence management in the elderly and should, therefore, be of interest to the National Institute of Aging. Phase I will prove the clinical feasibility of the monitor concept using an experimental PC-based bed-side prototype. The ambulatory product version of this instrument will be developed during Phase II.